Boiler system with spheroidal combustion chamber for liquid and gaseous fuels



H. GERBERT 3, 3 H 5 BER 3 Sheets-Sheet 1 Feb. 8, 1966 BOILER SYSTEM WIT PHEROIDAL COMBUSTION CHAM FOR LIQUID AND GASEOUS FUELS Filed Feb. 26, 1963 Feb. 8, 1966 H. GERBERT 3,233,596

BOILER SYSTEM WITH SPHEROIDAL COMBUSTION CHAMBER FOR LIQUID AND GASEOUS FUELS Filed Feb. 26, 1965 5 Sheets-Sheet 2 .717 venlar:

35/2 Gzaez? KEG/U T Feb. 8, 1966 H. GERBERT BOILER SYSTEM WITH SPHEROIDAL COMBUSTION CHAM FOR LIQUID AND GASEOUS FUELS Filed Feb. 26, 1963 Jnvenfor': lz-mi 6 5163527 United States Patent 5 Claims. cl: 122136) The present invention relates to boilers fired with liquid or gaseous fuels to heat water or other heatcarrying media. More specifically, this invention is concerned with the special design of a combustion chamber and the lines connected thereto.

In the past, boilers have been provided with a cylindrical or conical combustion chamber of the reversing type, which operates on the so-called three-flue principle, with the third flue arranged either helically or parallel to the boiler axis.

Owing to the high pressure drops of the flue gases, these conventional boilers have the disadvantage that they can be fired only with special high pressure burners which cause an extremely high pressure at the combustion start. Hence, special precautions have to be taken to prevent possible damages. Moreover, experience has shown that the burner mouth will be severely attacked by the heat of the reversing flame whereby the nozzle becomes deformed within a short period of time. As a consequence, the reversing flame can no longer fill up the flue completely and uniformly, and the flue is exposed to considerably irregular thermal stresses.

As compared with the amount of work and material required, these boilers have but a low efficiency and cannot be favorably operated under low-load conditions. Moreover, excessive amounts of soot will accumulate which are difficult to remove because of the adverse conditions under which the boiler systems have to be cleaned.

It is accordingly a primary object of this invention to provide a boiler having a wide range of capacity at approximately the same flue gas temperature, but without i the disadvantages inherent in conventional boilers.

It is another object of this invention to provide a boiler, whose combustion chamber and flues permit an optimum combustion of the fuel Without accumulation of soot.

It is another object of the invention to provide a boiler with two flues such that the external dimensions of the boiler are minimized.

Still another object of the invention is to increase the range of capacity of a boiler.

A further object of the invention is to provide a boiler of such a configuration as to achieve optimum flow conditions thereby reducing the pressure drops of the flue gases to a minimum.

Finally, it is an object of the invention to provide a boiler in accordance with the objects set forth above, whose external dimensions are as small as possible thereby minimizing the amount of material required for its construction.

The boiler according to the invention is provided with a combustion chamber of spheroidal shape. At one end of the chamber a burner is disposed, whose nozzle points toward the inside of the chamber, while at the opposite end an outlet passage is provided, which has a cross-sectional area smaller than that of the combustion chamber. The outlet passage is in communication with a deflection chamber, whose configuration insures optimum flow condition. The deflection chamber passes 3,233,596 Patented Feb. 8, 1966 over into at least one cylindrical flue surrounding the combustion chamber. In this flue, stabilizing members are provided, whose purpose is to stabilize the turbulence of the line gases passing therethrough.

The approximate ball shape of the combustion chamber insures a large chamber volume, at the same time minimizing the surface area, that is, the size of the chamber walls whereby under extremely heavy load conditions the combustion and the thermal effect on the chamber walls will be most favorable. As a result, the heat transfer inside the combustion chamber is greatly improved. In the flues communicating with the deflection chamber, similar results will be obtained by the acceleration of the flue gases, as they leave the combustion chamber through a constricted outlet passage and impinge upon a wall whereby they are deflected and a heavy turbulence is produced.

Prior to entering the flue, the gases are accelerated anew such that there is a turbulence throughout the annular flue gas chamber. This effect is achieved by proper calculation of the cross-sectional area of the annular chamber.

Another disadvantage of prior-art boiler systems is that the turbulence of the flue gases will vanish and the flow will become laminar, as the temperature and, consequently, the velocity of flow, decreases. To avoid this disadvantage, according to the invention, stabilizing members are inserted in the flues communicating with the deflection chamber. The purpose of these stabilizing members or plates is to maintain the turbulence of the flue gases and to permit the time during which the flue gases reside in the flues to be adjusted. Such an adjustment of the dwelling time has the advantage that the range of capacity of a standard boiler type can be considerably increased at about the same constant flue gas temperature, but without a change in the heating surface. Moreover, the stabilizing plates permit the resistance to the flow to be adjusted to any particular furnace-heat capacity.

Another advantage of the stabilizing plates is that they cause a certain predetermined pressure to be generated in the combustion chamber, which promotes the optimum combustion of the fuel, at the same time insuring that the amount of flue gases passing through the succeeding flues remain substantially constant. A further advantage of the adjustability of the boiler capacity is that the boiler can be adjusted so that it will operate satisfactorily both in winter and summer.

To avoid excessive ignition pressures and pulsations, and to insure a smooth combustion start, a flue-gas bypass is preferably provided in the boiler which, at the instant of ignition, insures that the pressure gradient between the combustion chamber and the boiler outlet is quickly balanced. The size or the bypass is such that only a negligible amount of flue gases can leave the boiler therethrough.

It will be understood that a boiler incorporating the features enumerated hereinbefore can also be equipped with a continuous flow heater or a hot-water tank directly attached to the boiler. In such a case, the continuous flow heater or the hot-water tank will be heated by the heat-carrying medium. To assist the natural water circulation, means are provided which permit the boiler to be slightly lifted toward its water outlet.

Two preferred embodiments of the invention will now be described in detail, by way of example only, reference being made to the accompanying drawings in which FIGURE 1 is a cross-sectional view of a boiler according to the invention, taken along line II in FIG. 2;

FIGURE 2 is a cross-sectional view of the boiler in FIG. 1, taken along line IIII in FIG. 1;

FIGURE 3 shows another embodiment of the invention with two flue-gas escape channels;

FIGURE 4 shows one arrangement of stabilizing members in the boilers of FIGS. 1 and 3; and

FIGURE 5 shows another arrangement of stabilizing members.

Referring now to FIG. 1, there is shown a shell 20 filled with water 21 in which the heating elements of the boiler are immersed. The elements include a combustion chamber 1 of spheroidal shape. At one end of the combustion chamber 1, a burner 2 is provided in such a manner that its nozzle or orifice points into the inside of chamber 1. Combustion chamber 1 is completely enclosed by a water jacket 3. At the diametrically Opposite end of chamher 1, the orifice of an outlet passage 4 is provided. The passage 4 is in communication with a deflection chamber 5, which, in turn is enclosed by water jackets 3 and 6. A flue 7 is provided which communicates with deflection cham ber 5. Flue 7 accommodates stabilizing members 3 which are arranged around the entire water jacket 3 and whose purpose is to maintain constant turbulent flow of the flue gases. Each stabilizing plate 8 has the shape of a segment of a flat ring and is held in place by securing or connecting rods 9, whereby a rigid plate structure is formed. As shown in F163. 4 and 5, the segments 8 may be inter connected in different ways. Water jackets 3 and 6 are connected by water-bearing channels 11, 11', while combustion chamber 1 directly communicates with flue 7 via a bypass 10. The boiler shell 20 is also provided in a conventional manner with a hot water outlet 12 and a reflux connection or Water feed inlet 13. Moreover, ad justing means 14 are provided, which serve to slightly tiit FIG. 3 shows another embodiment of the invention. In general, the structure of the boiler shown in FIG. 3 is similar to that of the boiler illustrated in FIGS. 1 and 2, except that deflection chamber 5 connects the combustion chamber with two coaxial flues 7'. Moreover, there is provided a continuous flow heater 15. To increase the heat transfer and the rigidity of the boiler structure, ribs 17 are provided at the rear of the boiler. The embodiment shown in FIG. 3 has the advantage that with an optimum utilization of the flue gases the external dimensions of the boiler are extremely small.

In the showing of FIG. 3 the circular segments for stabilizing the turbulence have been omitted, and it will be understood that their arrangement in flues 7' is the same as that in flue 7 (FIGS. 1 and 2).

In the embodiments shown the burner flame extends into the combustion chamber 1, which latter insures optimum combustion because of its spheroidal shape. Thus, the flue gases are partly deflected so that incompletely burned particles of the fuel will be returned to the fire zone. After leaving the combustion chamber 1 through the restricted outlet passage 4, the flue gases enter the deflection chamber 5 where they impinge upon a wall 5", whereby they are deflected. This deflection is accompanied by a heavy turbulence.

To improve the heat transfer, turbulent flow of the flue gases is further maintained by acceleration, as the gases enter the tides, and by the stabilizing segments 8 mounted inside the fiues 7, '7.

While the novel features of the invention as applied to two preferred embodiments have been shown and described, it will be obvious that modifications of the device illustrated may be made without departing from the spirit and the scope of the invention. Accordingly, the scope 4 of this invention is to be governed by the language of the following claims construed in the light of the foregoing description of this invention.

What I claim is:

1. In a boiler heated by the combustion of liquid and gaseous fuels, a boiler shell; and a system of heating elements in said shell, said system including a combustion chamber of substantially spheroidal shape, a burner, an outlet passage, said burner and said outlet passage respectively having orifices in diametrically opposite portions of said combustion chamber, said orifice of said outlet pasage having a cross-sectional area substantially smaller than that of said combustion chamber, a deflection chamber communicating with said outlet passage, a flue extending around said combustion chamber and communicating with said deflection chamber, and a plurality of stabilizing members mounted in said flue to maintain turbulent flow of flue gases therethrough.

2. In a boiler as set forth in claim 1, a by-pass conduit connecting the combustion chamber and said flue, said conduit having an orifice in a portion of said combustion chamber adjacent the orifice of said burner and remote from the orifice of said outlet passage.

3. In a boiler as set forth in claim 1, adjusting means for tilting said boiler shell.

4. in a boiler heated by the combustion of liquid and gaseous fuels, a boiler shell; a system of heating elements in said shell, said system including a combustion chamber of substantially spheroidal shape, a burner, an outlet passage, said burner and said outlet passage respectively having orifices in diametrically opposite portions of said combustion chamber, said orifice of said outlet passage having a cross-sectional area substantially smaller than that of said combustion chamber, a deflection chamber communicating with said outlet passage, at least one cylindrical flue extending around said combustion chamber and communicating with said deflection chamber, a plurality of stabilizing members mounted in said cylindrical flue to maintain turbulent flow of flue gases therethrough; and a continuous flow heater in said shell and outside said system of heating elements.

5. In a boiler as set forth in claim 1, said flue and said combustion chamber being spaced from each other, means for feeding water to said shell for thereby filling the space between said chamber and said flue with water to be heated by said system, and means for withdrawing the heated water.

References Cited by the Examiner UNITED STATES PATENTS 935,759 10/1909 Ingalls 122-135 2,040,959 5/1936 Schumann 122-136 2,232,546 2/1941 Marsh 122494 2,715,390 8/1955 Tenney et al. 12224 2,753,390 7/1956 Limes et al. 122-367 2,761,430 9/1956 Schaefer 122-494 3,007,457 11/ 1961 Ospelt 12237 FOREIGN PATENTS 55,950 6/1952 France. 57,328 10/1952 France.

787,261 7/1935 France. FREDERICK L. MATTESON, JR., Primary Examiner.

KENNETH W. SPRAGUE, PERCY L. PATRICK,

Examiners. 

1. IN A BOILER HEATED BY THE COMBUSTION OF LIQUID AND GASEOUS FUELS, A BOILER SHELL; AND A SYSTEM OF HEATING ELEMENTS IN SAID SHELL, SAID SYSTEM INCLUDING A COMBUSTION CHAMBER OF SUBSTANTIALLY SPHEROIDAL SHAPE, A BURNER, AN OUTLET PASSAGE, SAID BURNER AND SAID OUTLET PASSAGE RESPECTIVELY HAVING ORIFICES IN DIAMETRICALLY OPPOSITE PORTIONS OF SAID COMBUSTION CHAMBER, SAID ORIFICE OF SAID OUTLET PASSAGE HAVING A CROSS-SECTIONAL AREA SUBSTANTIALLY SMALLER THAN THAT OF SAID COMBUSTION CHAMBER, A DEFLECTION CHAMBER COMMUNICATING WITH SAID OUTLET PASSAGE, A FLUE EXTENDING AROUND SAID COMBUSTION CHAMBER AND COMMUNICATING WITH SAID DEFLECTION CHAMBER, AND A PLURALITY OF STABILIZING MEMBERS MOUNTED IN SAID FLUE TO MAINTAIN TURBULENT FLOW OF FLUE GASES THERETHROUGH. 